Turbine-blade structure



Nov. 20, 1923 H. F. SCHMIDT' TURBI NE BLADE STRUCTURE Filed April 16. 1920 IN V EN TOR.

Hem" F. Schmidt BY ,&1) g g ATTORNEY HENRY r. summer, or swasrnreosn, rnivnsvnvnnra, AssIenon TO WESTING- HOUSE ELECTRIC AND nanurnorennve ooiaraivr, A CORPORATION or rnnnsvn VANIA.

TURBINE-BLADE STRUCTURE.

Application filed April 16, 1920. Serial No. 374,373.

T 0 aZl whom it may cancer 21,:

Be it known that 1, Henry F. bcniinrr, a citizen of the United States, and a resident of Swarthmore, in the county of Delaware and State of Pennsylvania, have invented a new and useful Improvement in Turbine- Blade Structures, of which the following is a specification. This invention relates to turbines and it has for an object to produce a novel turbine Wheel and bucket suitable for impulse turbines.

More specifically the object of my inven tion is to produce a new and improved tur-' bine wheel arrangement 1n whlch the passages for motive fluid are formed between or in blades or buckets which are supported against centrifugal force in compression in stead of in tension,

These and other objects which will be made apparent throughout the further description of my invention are attained by means of apparatus embodying the features of my invention herein described and illustrated in the drawings accompanying and forming a part hereof. Y

My invention contemplates a turbine wheel in which the working elements are mounted on the inner periphery of a cylindrical or overhanging flange, whereby these elements are effectively supported in compression against centrifugal force. This method of securing or mounting the elements greatly simplifies the securin or mounting means. A further advantage of such aconstruction is that the elements may be made of relatively light material, such, for example, as pressed steel or bronze and nestedtogether on the inner periphery of the flange. My invention also contemplates a new and improved impulse bucketadapted for this construction.

In the drawings: Fig. l is a diagrammatic sectional view, along the line l1 of Fig. 2, of a turbine wheel arrangement embodyin the features of my invention.

ig. 2 is a sectional view along the line IL-II of Fig. 1.

.Fig. 3 is a perspective view of one of the buckets illustrated in operative position in Figs. 1 and 2.

n Fig. 1, I have illustrated a turbine wheel 5 as mounted on the overhanging end of a shaft 6. However, a shaft supported on both sides of the wheels 0 may be provided, if desired. The turblne whee illustrated is provided with an overhanging cylindrical flange or drum '7 on the innerperiphery of which the working elements are mounted. Preferably the flange 7 defines an internal channel 7 within which are located the bucket-forming elements hereinafter referred to.

The working elements illustrated consist of sheet metal impulse buckets 8 of the Pelton type, one of which is shown in detail in Fig. 3. These buckets are nested together, as shown in Fig. 2, so as to form a series of semi-circular motive fluidpassages which overlap each other and are inclined to the inner periphery ofthe flange 7. As shown, motive fluid is delivered at high velocity to one side of the buckets 8 by means of a nozzle 10 (shown in dotted lines in Fig. 2). The impulse of the jet of motive fluid striking the buckets, and the reaction due to the deflection of the jet around the semi-circular passage produce the force which causes the wheel 5 to rotate.

I have shown a reversing chamberv 11 for receiving-the motive fluid discharged from the inner side of the buckets 8 and for redirecting it into the buckets at a point farther along on the inner periphery of the flange 7. If desired, a plurality of reversing buckets may be employed so as to repeat the redirecting of the motive fluid into the buckets. This method of extracting the energy of the steam is familiar to those skilled in theart and requires no further description.

In the construction,illustrated, the buckets 8 are composed of bucket-forming elements 9 which rest upon one another in the channel 7 and define buckets or passages for the motive fluid. Each bucket-forming element 9 is preferably pressed into scoop form from sheet metal and, as may be seen from Fig. 3, comprises a bottom portion 9 and a semicircular flange portion 12 terminating in overhanging flanges 12 adapted to rest on shoulders 13, formed on the flange at the sides of the channel 7. The shoulders :13 are of such a height as to hold the inclined bucket-forming elements, with the semicircular ends resting at the bottom of the channel 7 and the flanges 12 on the shoulders 13, at the proper inclination to secure a correct operative position of the buckets as shown in Fig. 2. Also, I show caulking strips la extending along with the shoulders 13 which may be crimped over the flanges 1.2 of the bucket members 9 to secure the latter in. place. 7 v

The bucket forming element illustrated in Fig. 3 consists of a sheet metal stamping,

such as may be made in one or two operations of a. press. The bucket elements are shaped so as to automatically nest together when assembled, as shown in Fig. 2. It will be noted that the bucket elements rest against the inner periphery of the flange 7 and that the flanges 12 rest on the internal shoulders 13, consequently the buckets are supported against centrifugal force in compression instead of in tension, as is usually the case. For this reason more elaborate mounting means are unnecessary.

VVhile- I have shown my invention in but one form, it will be-obvious to those skilled inthe' art thatit is not so limited but is susceptible of various other changes and modifications, without departing from, the

spirit thereof anddesire therefore, that only'su'chlimitations shall be placed thereupon as are imposed by the prior art or as are specifically set forth in the appended claims.

\Vhat I claim is:

l. A turbine wheel having an overhang ing flange, shoulders on theinner periphery of said flange and sheet metal buckets nested within said flange and supported by the flange and the shoulders.

2. Ina turbine, the combination of a rotor provided with an internal bucket-holding channel, a series of contacting buckets in the channel and having their outer ends resting on the bottom of the channel, and a flange portion at the entrance ends of the buckets torsupporting the latter with respect to the sides of the channel. I

3. In a. turbine, the combination of a rotor provided with an internal channel having lateral shoulders and a series of inclined buckets resting at their outer ends on the bottom of the channel and having outwardly channel.

5. In a turbine, the combination oi a rotor havlng an internal channel provided with lateral shoulders, a series of inclined sheetmetal buckets inthe channel and having 7 their outer ends resting againstthe bottom of the channel, and outwardly pres-sod flanges at the inner ends 01": the buckets which rest onsaid shoulders.

6. In a turbine, the combination of a rotor having a channel provided with lateral shoulders, a series of buckets having like ends resting against the bottom of said channel, curved flanges at the other ends of the buckets resting on said" shoulders, and means on. the rotor for holdingsaid. first means in place with respect to said shoul ders.

7. turbine bucket elementof scoop fo-rm having a. bottom portion and a curved flange portion terminating ininclined overhanging flanges.

8. A turbine comprising a rotor having a flange defining an internal channel with lateral shoulders, a plurality oi buckets composed of bucket elements of scoop form having bottom portions and curved flange portions terminating in overhanging flanges, the bucket elements being disposed in an inclined manner in the channel with the bottom portions resting against the flange and cooperating with the semi-circular flanges to define motive-fluid passageways and with the over-hanging flanges resting on said shoulders,and a nozzle and reversing chamber cooperating with the buckets.

In testimony whereof, I have hereunto subscribed my name this March 3.0, 19-20 HENRY r. scHMm'r. 

